OpenGLRenderer.cpp revision bd6b79b40247aea7bfe13d0831c6c0472df6c636 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "OpenGLRenderer"
18
19#include <stdlib.h>
20#include <stdint.h>
21#include <sys/types.h>
22
23#include <utils/Errors.h>
24#include <utils/KeyedVector.h>
25#include <utils/Log.h>
26
27#include <GLES2/gl2.h>
28#include <GLES2/gl2ext.h>
29
30#include <SkCanvas.h>
31#include <SkPaint.h>
32#include <SkXfermode.h>
33
34#include "OpenGLRenderer.h"
35#include "Matrix.h"
36
37namespace android {
38namespace uirenderer {
39
40///////////////////////////////////////////////////////////////////////////////
41// Defines
42///////////////////////////////////////////////////////////////////////////////
43
44#define SV(x, y) { { x, y } }
45#define FV(x, y, u, v) { { x, y }, { u, v } }
46
47///////////////////////////////////////////////////////////////////////////////
48// Globals
49///////////////////////////////////////////////////////////////////////////////
50
51const SimpleVertex gDrawColorVertices[] = {
52        SV(0.0f, 0.0f),
53        SV(1.0f, 0.0f),
54        SV(0.0f, 1.0f),
55        SV(1.0f, 1.0f)
56};
57const GLsizei gDrawColorVertexStride = sizeof(SimpleVertex);
58const GLsizei gDrawColorVertexCount = 4;
59
60const TextureVertex gDrawTextureVertices[] = {
61        FV(0.0f, 0.0f, 0.0f, 1.0f),
62        FV(1.0f, 0.0f, 1.0f, 1.0f),
63        FV(0.0f, 1.0f, 0.0f, 0.0f),
64        FV(1.0f, 1.0f, 1.0f, 0.0f)
65};
66const GLsizei gDrawTextureVertexStride = sizeof(TextureVertex);
67const GLsizei gDrawTextureVertexCount = 4;
68
69///////////////////////////////////////////////////////////////////////////////
70// Shaders
71///////////////////////////////////////////////////////////////////////////////
72
73#define SHADER_SOURCE(name, source) const char* name = #source
74
75#include "shaders/drawColor.vert"
76#include "shaders/drawColor.frag"
77
78#include "shaders/drawTexture.vert"
79#include "shaders/drawTexture.frag"
80
81Program::Program(const char* vertex, const char* fragment) {
82    vertexShader = buildShader(vertex, GL_VERTEX_SHADER);
83    fragmentShader = buildShader(fragment, GL_FRAGMENT_SHADER);
84
85    id = glCreateProgram();
86    glAttachShader(id, vertexShader);
87    glAttachShader(id, fragmentShader);
88    glLinkProgram(id);
89
90    GLint status;
91    glGetProgramiv(id, GL_LINK_STATUS, &status);
92    if (status != GL_TRUE) {
93        GLint infoLen = 0;
94        glGetProgramiv(id, GL_INFO_LOG_LENGTH, &infoLen);
95        if (infoLen > 1) {
96            char* log = (char*) malloc(sizeof(char) * infoLen);
97            glGetProgramInfoLog(id, infoLen, 0, log);
98            LOGE("Error while linking shaders: %s", log);
99            delete log;
100        }
101        glDeleteProgram(id);
102    }
103}
104
105Program::~Program() {
106    glDeleteShader(vertexShader);
107    glDeleteShader(fragmentShader);
108    glDeleteProgram(id);
109}
110
111void Program::use() {
112    glUseProgram(id);
113}
114
115int Program::addAttrib(const char* name) {
116    int slot = glGetAttribLocation(id, name);
117    attributes.add(name, slot);
118    return slot;
119}
120
121int Program::getAttrib(const char* name) {
122    return attributes.valueFor(name);
123}
124
125int Program::addUniform(const char* name) {
126    int slot = glGetUniformLocation(id, name);
127    uniforms.add(name, slot);
128    return slot;
129}
130
131int Program::getUniform(const char* name) {
132    return uniforms.valueFor(name);
133}
134
135GLuint Program::buildShader(const char* source, GLenum type) {
136    GLuint shader = glCreateShader(type);
137    glShaderSource(shader, 1, &source, 0);
138    glCompileShader(shader);
139
140    GLint status;
141    glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
142    if (status != GL_TRUE) {
143        // Some drivers return wrong values for GL_INFO_LOG_LENGTH
144        // use a fixed size instead
145        GLchar log[512];
146        glGetShaderInfoLog(shader, sizeof(log), 0, &log[0]);
147        LOGE("Error while compiling shader: %s", log);
148        glDeleteShader(shader);
149    }
150
151    return shader;
152}
153
154DrawColorProgram::DrawColorProgram():
155        Program(gDrawColorVertexShader, gDrawColorFragmentShader) {
156    getAttribsAndUniforms();
157}
158
159DrawColorProgram::DrawColorProgram(const char* vertex, const char* fragment):
160        Program(vertex, fragment) {
161    getAttribsAndUniforms();
162}
163
164void DrawColorProgram::getAttribsAndUniforms() {
165    position = addAttrib("position");
166    color = addAttrib("color");
167    projection = addUniform("projection");
168    modelView = addUniform("modelView");
169    transform = addUniform("transform");
170}
171
172void DrawColorProgram::use(const GLfloat* projectionMatrix, const GLfloat* modelViewMatrix,
173        const GLfloat* transformMatrix) {
174    Program::use();
175    glUniformMatrix4fv(projection, 1, GL_FALSE, projectionMatrix);
176    glUniformMatrix4fv(modelView, 1, GL_FALSE, modelViewMatrix);
177    glUniformMatrix4fv(transform, 1, GL_FALSE, transformMatrix);
178}
179
180DrawTextureProgram::DrawTextureProgram():
181        DrawColorProgram(gDrawTextureVertexShader, gDrawTextureFragmentShader) {
182    texCoords = addAttrib("texCoords");
183    sampler = addUniform("sampler");
184}
185
186///////////////////////////////////////////////////////////////////////////////
187// Support
188///////////////////////////////////////////////////////////////////////////////
189
190const Rect& Snapshot::getMappedClip() {
191    if (flags & kFlagDirtyTransform) {
192        flags &= ~kFlagDirtyTransform;
193        mappedClip.set(clipRect);
194        transform.mapRect(mappedClip);
195    }
196    return mappedClip;
197}
198
199///////////////////////////////////////////////////////////////////////////////
200// Constructors/destructor
201///////////////////////////////////////////////////////////////////////////////
202
203OpenGLRenderer::OpenGLRenderer() {
204    LOGD("Create OpenGLRenderer");
205
206    mDrawColorShader = new DrawColorProgram;
207    mDrawTextureShader = new DrawTextureProgram;
208}
209
210OpenGLRenderer::~OpenGLRenderer() {
211    LOGD("Destroy OpenGLRenderer");
212}
213
214///////////////////////////////////////////////////////////////////////////////
215// Setup
216///////////////////////////////////////////////////////////////////////////////
217
218void OpenGLRenderer::setViewport(int width, int height) {
219    glViewport(0, 0, width, height);
220
221    mat4 ortho;
222    ortho.loadOrtho(0, width, height, 0, -1, 1);
223    ortho.copyTo(mOrthoMatrix);
224
225    mWidth = width;
226    mHeight = height;
227}
228
229void OpenGLRenderer::prepare() {
230    mSnapshot = &mFirstSnapshot;
231    mSaveCount = 0;
232
233    glDisable(GL_SCISSOR_TEST);
234
235    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
236    glClear(GL_COLOR_BUFFER_BIT);
237
238    glEnable(GL_SCISSOR_TEST);
239    glScissor(0, 0, mWidth, mHeight);
240
241    mSnapshot->clipRect.set(0.0f, 0.0f, mWidth, mHeight);
242}
243
244///////////////////////////////////////////////////////////////////////////////
245// State management
246///////////////////////////////////////////////////////////////////////////////
247
248int OpenGLRenderer::getSaveCount() const {
249    return mSaveCount;
250}
251
252int OpenGLRenderer::save(int flags) {
253    return saveSnapshot();
254}
255
256void OpenGLRenderer::restore() {
257    if (mSaveCount == 0) return;
258
259    if (restoreSnapshot()) {
260        setScissorFromClip();
261    }
262}
263
264void OpenGLRenderer::restoreToCount(int saveCount) {
265    if (saveCount <= 0 || saveCount > mSaveCount) return;
266
267    bool restoreClip = false;
268
269    while (mSaveCount != saveCount - 1) {
270        restoreClip |= restoreSnapshot();
271    }
272
273    if (restoreClip) {
274        setScissorFromClip();
275    }
276}
277
278int OpenGLRenderer::saveSnapshot() {
279    mSnapshot = new Snapshot(mSnapshot);
280    return ++mSaveCount;
281}
282
283bool OpenGLRenderer::restoreSnapshot() {
284    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
285    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
286
287    sp<Snapshot> current = mSnapshot;
288    sp<Snapshot> previous = mSnapshot->previous;
289
290    if (restoreLayer) {
291        // Unbind current FBO and restore previous one
292        // Most of the time, previous->fbo will be 0 to bind the default buffer
293        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
294
295        const Rect& layer = current->layer;
296        clipRect(layer.left, layer.top, layer.right, layer.bottom);
297        mSnapshot->transform.loadIdentity();
298
299        drawTextureRect(0.0f, 0.0f, mWidth, mHeight, current->texture, current->alpha);
300
301        glDeleteFramebuffers(1, &current->fbo);
302        glDeleteTextures(1, &current->texture);
303    }
304
305    mSnapshot = previous;
306    mSaveCount--;
307
308    return restoreClip;
309}
310
311///////////////////////////////////////////////////////////////////////////////
312// Layers
313///////////////////////////////////////////////////////////////////////////////
314
315int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
316        const SkPaint* p, int flags) {
317    // TODO Implement
318    return saveSnapshot();
319}
320
321int OpenGLRenderer::saveLayerAlpha(float left, float top, float right, float bottom,
322        int alpha, int flags) {
323    int count = saveSnapshot();
324
325    mSnapshot->flags |= Snapshot::kFlagIsLayer;
326    mSnapshot->alpha = alpha / 255.0f;
327    mSnapshot->layer.set(left, top, right, bottom);
328
329    // Generate the FBO and attach the texture
330    glGenFramebuffers(1, &mSnapshot->fbo);
331    glBindFramebuffer(GL_FRAMEBUFFER, mSnapshot->fbo);
332
333    // Generate the texture in which the FBO will draw
334    glGenTextures(1, &mSnapshot->texture);
335    glBindTexture(GL_TEXTURE_2D, mSnapshot->texture);
336
337    // The FBO will not be scaled, so we can use lower quality filtering
338    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
339    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
340
341    // TODO ***** IMPORTANT *****
342    // Creating a texture-backed FBO works only if the texture is the same size
343    // as the original rendering buffer (in this case, mWidth and mHeight.)
344    // This is expensive and wasteful and must be fixed.
345
346    const GLsizei width = mWidth; //right - left;
347    const GLsizei height = mHeight; //bottom - right;
348
349    const GLint format = (flags & SkCanvas::kHasAlphaLayer_SaveFlag) ? GL_RGBA : GL_RGB;
350    glTexImage2D(GL_TEXTURE_2D, 0, format, width, height, 0, format, GL_UNSIGNED_BYTE, NULL);
351    glBindTexture(GL_TEXTURE_2D, 0);
352
353    // Bind texture to FBO
354    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
355            mSnapshot->texture, 0);
356
357    GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
358    if (status != GL_FRAMEBUFFER_COMPLETE) {
359        LOGD("Framebuffer incomplete %d", status);
360
361        glDeleteFramebuffers(1, &mSnapshot->fbo);
362        glDeleteTextures(1, &mSnapshot->texture);
363    }
364
365    return count;
366}
367
368///////////////////////////////////////////////////////////////////////////////
369// Transforms
370///////////////////////////////////////////////////////////////////////////////
371
372void OpenGLRenderer::translate(float dx, float dy) {
373    mSnapshot->transform.translate(dx, dy, 0.0f);
374    mSnapshot->flags |= Snapshot::kFlagDirtyTransform;
375}
376
377void OpenGLRenderer::rotate(float degrees) {
378    mSnapshot->transform.rotate(degrees, 0.0f, 0.0f, 1.0f);
379    mSnapshot->flags |= Snapshot::kFlagDirtyTransform;
380}
381
382void OpenGLRenderer::scale(float sx, float sy) {
383    mSnapshot->transform.scale(sx, sy, 1.0f);
384    mSnapshot->flags |= Snapshot::kFlagDirtyTransform;
385}
386
387void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
388    mSnapshot->transform.load(*matrix);
389    mSnapshot->flags |= Snapshot::kFlagDirtyTransform;
390}
391
392void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
393    mSnapshot->transform.copyTo(*matrix);
394}
395
396void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
397    mat4 m(*matrix);
398    mSnapshot->transform.multiply(m);
399    mSnapshot->flags |= Snapshot::kFlagDirtyTransform;
400}
401
402///////////////////////////////////////////////////////////////////////////////
403// Clipping
404///////////////////////////////////////////////////////////////////////////////
405
406void OpenGLRenderer::setScissorFromClip() {
407    const Rect& clip = mSnapshot->getMappedClip();
408    glScissor(clip.left, mHeight - clip.bottom, clip.getWidth(), clip.getHeight());
409}
410
411const Rect& OpenGLRenderer::getClipBounds() {
412    return mSnapshot->clipRect;
413}
414
415bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
416    /*
417     * The documentation of quickReject() indicates that the specified rect
418     * is transformed before being compared to the clip rect. However, the
419     * clip rect is not stored transformed in the snapshot and can thus be
420     * compared directly
421     *
422     * The following code can be used instead to performed a mapped comparison:
423     *
424     *     mSnapshot->transform.mapRect(r);
425     *     const Rect& clip = mSnapshot->getMappedClip();
426     *     return !clip.intersects(r);
427     */
428
429    Rect r(left, top, right, bottom);
430    return !mSnapshot->clipRect.intersects(r);
431}
432
433bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom) {
434    bool clipped = mSnapshot->clipRect.intersect(left, top, right, bottom);
435    if (clipped) {
436        mSnapshot->flags |= Snapshot::kFlagClipSet;
437        setScissorFromClip();
438    }
439    return clipped;
440}
441
442///////////////////////////////////////////////////////////////////////////////
443// Drawing
444///////////////////////////////////////////////////////////////////////////////
445
446void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
447    // TODO: Set the transfer mode
448    const Rect& clip = mSnapshot->clipRect;
449    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color);
450}
451
452void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, const SkPaint* p) {
453    // TODO Support more than  just color
454    // TODO: Set the transfer mode
455    drawColorRect(left, top, right, bottom, p->getColor());
456}
457
458void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom, int color) {
459    GLfloat a = ((color >> 24) & 0xFF) / 255.0f;
460    GLfloat r = ((color >> 16) & 0xFF) / 255.0f;
461    GLfloat g = ((color >>  8) & 0xFF) / 255.0f;
462    GLfloat b = ((color      ) & 0xFF) / 255.0f;
463
464    mModelView.loadTranslate(left, top, 0.0f);
465    mModelView.scale(right - left, bottom - top, 1.0f);
466
467    mDrawColorShader->use(&mOrthoMatrix[0], &mModelView.data[0], &mSnapshot->transform.data[0]);
468
469    const GLvoid* p = &gDrawColorVertices[0].position[0];
470
471    glEnableVertexAttribArray(mDrawColorShader->position);
472    glVertexAttribPointer(mDrawColorShader->position, 2, GL_FLOAT, GL_FALSE,
473            gDrawColorVertexStride, p);
474    glVertexAttrib4f(mDrawColorShader->color, r, g, b, a);
475
476    glDrawArrays(GL_TRIANGLE_STRIP, 0, gDrawColorVertexCount);
477
478    glDisableVertexAttribArray(mDrawColorShader->position);
479}
480
481void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
482        GLuint texture, float alpha) {
483    mModelView.loadTranslate(left, top, 0.0f);
484    mModelView.scale(right - left, bottom - top, 1.0f);
485
486    mDrawTextureShader->use(&mOrthoMatrix[0], &mModelView.data[0], &mSnapshot->transform.data[0]);
487
488    // TODO Correctly set the blend function
489    glEnable(GL_BLEND);
490    glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
491
492    glBindTexture(GL_TEXTURE_2D, texture);
493
494    glActiveTexture(GL_TEXTURE0);
495    glUniform1i(mDrawTextureShader->sampler, 0);
496
497    const GLvoid* p = &gDrawTextureVertices[0].position[0];
498    const GLvoid* t = &gDrawTextureVertices[0].texture[0];
499
500    glEnableVertexAttribArray(mDrawTextureShader->position);
501    glVertexAttribPointer(mDrawTextureShader->position, 2, GL_FLOAT, GL_FALSE,
502            gDrawTextureVertexStride, p);
503
504    glEnableVertexAttribArray(mDrawTextureShader->texCoords);
505    glVertexAttribPointer(mDrawTextureShader->texCoords, 2, GL_FLOAT, GL_FALSE,
506            gDrawTextureVertexStride, t);
507
508    glVertexAttrib4f(mDrawTextureShader->color, 1.0f, 1.0f, 1.0f, alpha);
509
510    glDrawArrays(GL_TRIANGLE_STRIP, 0, gDrawTextureVertexCount);
511
512    glDisableVertexAttribArray(mDrawTextureShader->position);
513    glDisableVertexAttribArray(mDrawTextureShader->texCoords);
514
515    glBindTexture(GL_TEXTURE_2D, 0);
516    glDisable(GL_BLEND);
517}
518
519}; // namespace uirenderer
520}; // namespace android
521